1. Field of the Invention
The invention relates to digging equipment, and in particular, to equipment for trenching.
2. Description of the Related Art
Trenchers are used in landscaping to define beds, dig ditches for the bases of walls, allow insertion of edging and the like. Trenchers also are used by electricians and utilities to install cables or wiring in small trenches in the ground.
The trenchers available in the past, such as those shown in U.S. Pat. Nos. 4,503,630 and 5,226,248 have several common problems. First, the blades for the systems are off-center from the wheels. This creates a potential imbalance in the system, which can be particularly troublesome on hills. This problem is largely caused because the prior art systems are steered from the back, and the steering wheel cannot be directly behind the arbor, because that is where the trench is. Second, the blades, while adjustable in height, are fixed once adjusted. No provision is made to allow retraction if the blades hit an obstruction in the ground, such as a large rock. This means the user must constantly be on guard against such a possibility to avoid damaging the machine, and must manually move past or around the obstacle. Last, all of the currently available systems lift dirt out of the trench and deposit it immediately adjacent to the trench. From this location, dirt frequently is knocked or falls back into the trench.